1. Field of the Invention
The present invention relates to a planar inverted F antenna (PIFA) for wireless communication devices such as wireless modems, cellular telephones, personal digital assistants, etc. More particularly, the present invention relates to a method of providing multiple band response in a single antenna package.
2. Description of the Related Art
Recently, there has been an increasing thrust in the application of internal antennas in wireless communications. The concept of an internal antenna stems from the avoidance of using an external radiating element through the integration of the antenna into the communication device itself. Internal antennas have several advantageous features such as being less prone to external damage, a reduction in overall size of the communication device with optimization, and easy portability. In most internal antennas, the printed circuit board of the communication device serves as the ground plane of the internal antenna. Among the various choices for internal antennas, a PIFA appears to have great promise. The PIFA is characterized by many distinguishing properties such as relative lightweight, ease of adaptation and integration into the device chassis, moderate range of bandwidth, omni-directional radiation patterns in orthogonal principal planes for vertical polarization, versatility of optimization, and multiple potential approaches for size reduction. Its sensitivity to both vertical and horizontal polarization is of immense practical importance in mobile cellular/RF data communication applications because of the absence of the fixed antenna orientation as well as the multi-path propagation conditions. All these features render the PIFA to be a good choice as an internal antenna for mobile cellular/RF data communication applications.
In this invention, a new method of combining several planar inverted F and/or inverted F antennas in a single antenna unit is proposed. Several radiating patches are mounted on a common antenna carrier. The patches are made of materials suitable for use as connectors. The means of connecting the antenna to a PCB are described so that the integrated antenna can be mounted on a PCB using standard surface-mount techniques.
The principal objective of this invention is to provide a simple, low-cost means of providing a combination of planar inverted F antennas (PIFAs) and/or inverted F antennas (IFAs) in a single antenna package.
A further objective of the invention is to enable greater flexibility in the design of the radiating elements of an antenna to provide multi-band response, particularly in providing, for example, ISM frequency band response combined with standard cellular telephone frequency response.
Yet another objective is to provide means of attaching several radiating patches to a single antenna carrier.
These and other objects will be apparent to those skilled in the art.